Apparatus for distributing errors in the formation of helically wound container bodies

ABSTRACT

In the formation of helically wound containers by first winding a &#39;&#39;&#39;&#39;stick&#39;&#39;&#39;&#39; consisting of connected container bodies, the error in each body accumulates throughout the length of the &#39;&#39;&#39;&#39;stick.&#39;&#39;&#39;&#39; The error in each body is confined to such body by properly positioning each of an array of cutters, so as to sever the connected bodies into discrete bodies each having the individual error therein. The error in each body is readily accommodated in conventional closing machines, and there is no need to waste a trim ring when each stick is formed. All container bodies are thus identical in appearance, especially important when a label is helically wound. Each of the cutters is mounted on a carriage movable along a pinion axis indexed to an error-distributing position, the pinion moving between a pair of racks engaging a group of such errorcorrecting pinions. The latter are each spaced a distance corresponding to the proper length of the container body plus or minus the error therein. The pitch diameter of the pinions varies from a minimum to a maximum according to the error accumulating in the formation of the stick.

United States Patent Lindberg APPARATUS FOR DISTRIBUTING ERRORS IN THEFORMATION OF HELICALLY WOUND CONTAINER BODIES [4 1 Jan. 25, 1972 PrimaryExaminerBernard Stickney Attorney-Carpenter, Ostis & Lindberg In theformation of helically wound containers by first winding a stick"consisting of connected container bodies, the error in each bodyaccumulates throughout the length of the stick." The error in each bodyis confined to such body by properly positioning each of an array ofcutters, so as to sever the connected bodies into discrete bodies eachhaving the individual error therein. The error in each body is readilyaccommodated in conventional closing machines, and there is no need towaste a trim ring when each stick is formed. All container bodies arethus identical in appearance, especially important when a label ishelically wound.

ABSTRACT Each of the cutters is mounted on a carriage movable along apinion axis indexed to an error-distributing position, the pinion movingbetween a pair of racks engaging a group of such error-correctingpinions. The latter are each spaced a distance corr esponding to theproper length of the container body plus or minus the error therein. Thepitch diameter of the pinions varies from a minimum to a maximumaccording to the error accumulating in the formation of the stick.

: 5 Claims, 5 Drawing Figures APPARATUS FOR DISTRIBUTING ERRORS IN THEFORMATION OF I-IELICALLY WOUND CONTAINER BODIES BACKGROUND OF THEINVENTION 1 Field of the Invention This invention relates generally toapparatus for forming a container body by helically winding at least onelamina on a fixed mandrel and moving a stick thus formed longitudinallyof such mandrel. The stick is later moved on to a rotating mandrel whichserves as an anvil where the stick is cut into discrete lengthsaccording to the invention. The wound lamina has repetitive indiciathereon marking the beginning and end of a plurality of the discretecylinders to be cut from the stick. The apparatus according to presentinvention enables the error in the winding to be distributed properlyinto each cylinder after a number have been formed in the windingoperation.

2. The Prior Art Apparatus for distributing errors of the kind mentionedabove is best exemplified in Brigham U.S. Pat. No. 3,158,074 in Class93; Subclass 80. That patent shows a pantograph arrangement fordistributing the error.

SUMMARY OF THE INVENTION The apparatus according to the presentinvention constitutes an improvement over the prior art in that the useof a many-jointed linkage mechanism is avoided.

THE DRAWINGS FIG. 1 is a schematic elevational view of a machine forforming helically wound can bodies having the improvements according tothe present invention embodied therein;

FIG. 2 is a plan view, to an enlarged scale, of a portion of the machineseen in FIG. 1, and showing a cutter array for cutting a "stick ofcontainer bodies into discrete lengths;

FIG. 3 is a side elevational view looking in the direction of the arrows3-3 of FIG. 2;

FIG. 4 is a schematic view of a stick of containers trimmed to length inaccordance with what is known in the prior art as the planned trimmedmethod"; and

FIG. 5 is a view similar to FIG. 4 showing the manner in which thecontainer bodies are cut to proper length by the structure according tothe present invention.

The apparatus for distributing errors in the formation of helicallywound container bodies is denoted generally by the reference numeral andincludes a fixed arbor or mandrel 11.

After the wound container bodies are formed in the fixed mandrel theymove on to a rotating mandrel 11A turning with a driving shaft 13nesting within fixed mandrel 11. A driving sprocket 14 is fixed upon theshaft 13 and is driven by a chain 16. One or more base strips of fibrousmaterial such as paper 17 may be helically wound on the mandrel 11, anda pattern strip 18 is wound upon the tube formed by the winding of thebase strips 17. The pattern strip 18 is fed on to the base tube in thesame spiral angle or pitch as the base tube, being normally offset withrespect to the seam formed on the outside of the base tube. Theapplication of the pattern strip 18 to the base tube produces asuccession of patterns upon the outside of the tube.

A crossbelt 19 is trained about spaced pulleys 22 and 23 and turns orrotates the tube 21 on the mandrel l1, and advances the formed tubeforwardly along the rotating mandrel 11A to the right as seen in FIG. 1.Pulley 24 has a bevel gear 24 fixed thereto, meshing with a bevel gear24A fixed on a driving shaft 26.

It may be noted that the rotation of mandrel 11A and the driving of thepulleys 22 and 23 is effected by driving motors, not shown, and wellknown in the prior art, and they are accordingly not shown herein.

In the forming of the tube 21 and the winding the pattern strip 18therearound a plurality of regularly spaced indicia I are formed betweenadjacent container body lengths C. It may also be noted that thewrapping of the successive layers about mandrels 11 and 11A may beconcomitant with gluing mechanisms well known in the prior art. They areaccordingly not described herein.

Desirably, the length of each container bodies C is a constant, but byreason of variations in printing and variations in temperature andhumidity of the ambient in which the container bodies are being formedand variations in specification of the strips being wound on the arborII, the length of each container body C may be greater or less than adesired amount. The error in the length of the can bodies C iscumulative as the stick moves along mandrel 11A.

It is to the proportioning of this error into each of the containerbodies C that this invention is directed.

Accordingly, structure is provided for proportioning and distributingthe total error in a stick into the container bodies C. To this endthere is provided a fixed carriage 27 supporting an array of cutters 28.These are mounted on a flying carriage 29 having supports 31 with wheels32 at the lower ends thereof for supporting the flying carriage 29 onthe fixed carriage 27.

Structure is provided for moving the flying carriage 29 with respect tothe fixed carriage 27, and to this end a lead screw 33 cooperates with afixed nut secured to the underside of the flying carriage 29. Therotating lead screw 33 has a sprocket 36 fixed to one end thereof, and asprocket chain 37 turns the lead screw 34 which is joumaled in supports35 at each end of the fixed carriage 27.

The cutters for cutting the stick into the discrete container bodies Ceach consists of a circular cutting knife 38 mounted in clevis 39supporting an idler shaft 40 for the circular cutter 38. A stub shaft 41extends from the base of each clevis 39 and has a pinion 42 rotatablysupported thereon. The pinions 42 are adapted to rotate between a lowerrack 43 formed as part of the flying carriage 29 and an upper rack 44.

The pitch diameters of the pinions 42 increase in viewing the same fromthe right to the left as seen in FIGS. I and 2, and the upper rack 44therefor diverges slightly with respect to lower rack 43.

Extreme right-hand cutter 38 is arranged to sense the indicia I betweenthe first and second container body C viewing the same from the right toleft as seen in FIG. 2. The clevis 39 mounting the cutter 40 at suchjuncture between the first and second container bodies is best seen inFIG. 3. Clevis 39 has a bracket arm 48 extending upward therefrom whichis in overlying relationship to the stick supported on the rotatingmandrel 11A. Bracket arm 48 has a light source 49 secured thereto whichcauses a light beam emanating therefrom to impinge against the surfaceof the tube 21. The light is reflected therefrom into a photoelectriccell PE, the output of which is connected by leads 53 to a controlcircuit 52 connection to supply leads 56 to a source of power seen inFIG. 1.

The control circuit 52 has a double function, one being to energize amotor 46 turning a shaft 45 made fast to the pinion 42 associatedtherewith, said pinion being at the right end of the array 28 of thecutters 38. Motor 46 is braced in position by a bracket arm 47 securedat its ends to motor 46 and bracket arm 48.

The other function of the control circuit 52 is to energize a circuitincluding leads 50 to control the operation of the lead screw 33controlling the movement of the flying carriage 29. The details of suchcontrol circuit and the control of flying carriage 29 are bestillustrated in Brigham U.S. Pat. No. 3,158,074.

The energization of the motor 46 causes the pinion 42 driven thereby tomove the right-hand-most cutter of the array 28 into a position ofregister with the indicia marked I between the first and secondcontainer bodies. The rotation of said pinion causes the upper rack 44to move translatively through a distance which is twice the movement ofthe center of the shaft 45 and the pinion 42 thereon. This causes eachof the successive pinions 42 at the ends of can bodies C from number oneto through number eight of the can bodies C to be in register with theindicias I and ready for subsequent movement to sever the stick intodiscrete container bodies.

Consider now an assumption that the maximum accumulative error informing a "stick of eight bodies to be 0.250 inch. That error divided bya total of eight bodies comprising the stick" results in an error alength of each of the bodies equal to 0.031 inch. That error in eachbody must be accompanied by a movement of the center of each successivepinion by an amount equal to the position of the pinion times the errorin each body. Thus, the error existing in the stick" between containerbody three and container body four is equal 3 times 0.031 inch or 0.093inch. Accordingly, each of the pinions must have its center translatableby an amount equal to the error in each container body times itsposition on the stick as measured from the free end of such stick. Itwill be apparent, it is believed, that the pitch diameter of each pinionmust increase by an amount equal to twice the error existing at theparticular body, which gives a movement to the corresponding pinioncenter equal to the error existing in such container body end.

It will be appreciated that the selected error for a stick of eightcontainer bodies may be plus or minus such selected error and that themovement of the pinion center and corresponding cutter 38 carriedthereat will be approximate only.

Structure is provided for ensuring that the operation of the array ofcutters takes place only when a completed stick containing eightconnected container bodies is ready for cutting. To this end a similarbracket 49A is mounted at the eighth of the array of the cutters 28, theleftmost one as seen in FIGS. 1 and 2. Bracket 48A has a light source49A thereon, the light from which is reflected from the stick 21 into aphotoelectric cell, not shown, connected by leads 55A into a controlcircuit 57 having a power supply connected by the leads S6 thereto. Theoutput from the control circuit 57 is connected by output leads 58 tostructure which controls the operation of the flying carriage 29. Theoutput signal from control circuit 57 also cooperates with the controlsignal supplied by the output leads 50 from the control signal suppliedby the output leads 50 from the control circuit 52. When the extremeright-hand cutter 44 of the array 28 is in register with the indicia Imarking the point for severing the first container body from the secondcontainer body, and when the eighth cutter 38 of the array 28 is inalignment with the indicia I marking the point of severance between theeighth containers body and the first container body of a successivestick, all of the intervening cutters 38 and the pinions 42 for movingsame are in a position of alignment with the indicia I marking the pointof severance between adjacent container bodies.

Structure not shown, is provided for moving the flying carriage 29 andthe fixed carriage 27 laterally of the axis of the mandrel 11A and thetube 21 being formed thereon, to cause the cutters 38 to move againstthe tube 21 and separate the stick into discrete container bodies.Structure for providing such movement of the cutter array 28 is wellknown in the art, and shown in the aforesaid Brigham patent.

The results obtained by the structure according to the present inventionmay be compared with the structure for which has been determined in theart the planned trim" ind method. Such is seen in FIG. 4, and the cutterarray 28 has the cutters 38 thereof a fixed distance apart. The centerone of such group of cutters is arranged to register with the indicia Imarking the line of severance between container bodies four and five,the control of the cutter array 28 being achieved in part by a controllamp C.L. made a part of control circuitry well known in the art. Thestick of containers 2] seen in FIG. 4 has an accumulative error likethat as seen in FIGS. 1 and 2, each container body having an errortherein for purposes of discussion hereat equal to 0.031 inch. Thecutters being 9 inches apart, for example, the error accumulating ineach half stick being 0.125 inch approximately. This results in thenecessity of cutting a trim ring equal to 0.250 inch in length.

Each of the container bodies to each side of the centermost cutter 38has its pattern strip 18 slightly out of register as seen in FIG. 4, theamount of misregister increasing to each side of the centermost cutter38.

Contrast the result achieved with the structure seen in FIG. 4 with thatachieved by the structure according to the present invention. As seen inFIG. 5, each container body C is identical in appearance to all othercontainer bodies, the error accumulating in the forming of the stickbeing proportioned and being distributed to the individual containerbodies.

I claim:

1. In a machine for the production of helically wound tubular bodiesfrom strip material, said machine including:

a. means for winding strip material on a mandrel to form a tube havingrecurring registration indicia thereon and for moving the tube axiallyalong the mandrel;

b. cutting means positioned adjacent the tube for severing tubularbodies therefrom;

c. said cutting means comprising individual cutters mounted for axialmovement relative to each other according to the distance betweenadjacent indicia of the tube; the improvement in structure forefi'ective movement of said cutters in the manner aforesaid whichcomprises:

e. a double rack having pinion means therebetween for providing movementto said cutters to space same by distances corresponding to the distancebetween the indicia on said tube;

f. means for supporting each of said cutters including a pinion of saidpinion means;

. motor means for rotating one of said pinions to follow the indiciabetween a pair of adjacent tubular bodies of said tube to cause saidother pinions and the cutters cooperating therewith to adopt positionsfor cutting said tubular bodies to a length inclusive of the variationtherein.

2. The invention according to claim 1 wherein said cutters are mountedas an array of same and are movable against said tube for cutting thesame into discrete lengths.

3. The invention according to claim 1 wherein said motor I means iscontrolled by photoelectric means.

4. The invention according to claim 3 wherein said photoelectric meansis connected to circuit means controlling said motor means.

5. The invention according to claim 1 wherein one of said racks movesaxially in accordance with the axial movement of said tube.

1. In a machine for the production of helically wound tubular bodiesfrom strip material, said machine including: a. means for winding stripmaterial on a mandrel to form a tube having recurring registrationindicia thereon and for moving the tube axially along the mandrel; b.cutting means positioned adjacent the tube for severing tubular bodiestherefrom; c. said cutting means comprising individual cutters mountedfor axial movement relative to each other according to the distancebetween adjacent indicia of the tube; d. the improvement in structurefor effective movement of said cutters in the manner aforesaid whichcomprises: e. a double rack having pinion means therebetween forproviding movement to said cutters to space same by distancescorresponding to the distance between the indicia on said tube; f. meansfor supporting each of said cutters including a pinion of said pinionmeans; g. motor means for rotating one of said pinions to follow theindicia between a pair of adjacent tubular bodies of said tube to causesaid other pinions and the cutters cooperating therewith to adoptpositions for cutting said tubular bodies to a length inclusive of thevariation therein.
 2. The invention according to claim 1 wherein saidcutters are mounted as an array of same and are movable against saidtube for cutting the same into discrete lengths.
 3. The inventionaccording to claim 1 wherein said motor means is controlled byphotOelectric means.
 4. The invention according to claim 3 wherein saidphotoelective means is connected to circuit means controlling said motormeans.
 5. The invention according to claim 1 wherein one of said racksmoves axially in accordance with the axial movement of said tube.